1500 years old, this ancient Chinese text is still utilized by both militaries and business schools around the world.

And it should be — research shows those unconventional tactics work.

When Davids don't fight by Goliaths' rules they win 63 percent of battles.

When the political scientist Ivan Arreguín-Toft did the calculation a few years ago, what he came up with was 71.5 percent. Just under a third of the time, the weaker country wins. Arreguín-Toft then asked the question slightly differently. What happens in wars between the strong and the weak when the weak side does as David did and refuses to fight the way the bigger side wants to fight, using unconventional or guerrilla tactics? The answer: In those cases, the weaker party's winning percentage climbs from 28.5 percent to 63.6 percent. [David and Goliath: Underdogs, Misfits, and the Art of Battling Giant]

If the U.S. and Canada went to war and Canada chose to fight Sun Tzu-style, what would happen? The smart money would bet on Canada.

I believe Sun Tzu'sThe Art of War is the essential strategy guide of our time. Why?

We are relentlessly reminded this is the "information age."

Well, one of the primary themes of Sun Tzu's classic strategy guide is: the power of information.

I know: You're not a general or a CEO. But we all wage metaphorical "wars" all day long.

"Fighting" to get that promotion or new job? Waging a pitched "battle" with your significant other over a delicate issue?

Sun Tzu can help you claim victory in all those skirmishes. And scientific research agrees with him. Let's dive in.

Knowledge is power

The crucial theme throughout the The Art of War is the power of accurate information.

Re-reading the book I was struck by how Sun Tzu hits this one idea again and again from so many angles.

He really doesn't beat around the bush: knowledge wins wars.

If you know the enemy and know yourself, you need not fear the result of a hundred battles. If you know yourself but not the enemy, for every victory gained you will also suffer a defeat. If you know neither the enemy nor yourself, you will succumb in every battle. [The Art of War]

Do you need infantry? Maybe. Snipers? Perhaps. Pilots? Could be.

What do you definitely need? Spies to get you information.

Unless you are kept informed of the enemy's condition, and are ready to strike at the right moment, a war may drag on for years. The only way to get this information is to employ spies, and it is impossible to obtain trustworthy spies unless they are properly paid for their services. [The Art of War]

Sun Tzu does not believe in fighting fair. He feels deception is at the very heart of war. But what is deception?

All it means is making sure your information is accurate and your enemy's is not.

Hence, when able to attack, we must seem unable; when using our forces, we must seem inactive; when we are near, we must make the enemy believe we are far away; when far away, we must make him believe we are near. Hold out baits to entice the enemy. Feign disorder, and crush him. [The Art of War]

One of the factors that make a general great, and therefore make him rare, is that he can withstand the urge of most men to rush headlong into direct engagements and can see instead how he can go around rather than through his opponent… B. H. Liddell Hart epitomizes much military wisdom in two axioms. The successful general, he says, chooses the line or course of least expectation and he exploits the line of least resistance. [How Great Generals Win]

You might argue that back then information was so important because it was scarce. We're drowning in information now. So maybe it's no longer a problem…

But research actually shows nothing has changed since Sun Tzu's era. In fact, the problem may have gotten worse.

Sun Tzu for the 21st Century

Google brings us a library full of data with a keystroke. Our bursting inboxes scream "information overload."

The breadth of topics in these discussions is extremely wide. The GMs do not limit their focus to planning, business strategy, staffing, and other "top management concerns." They discuss virtually anything and everything even remotely associated with their businesses and organizations…. In these conversations, GMs typically ask a lot of questions. In a half-hour conversation, some will ask literally hundreds. [John P. Kotter on What Leaders Really Do]

The primary challenge of a leader has not changed much since Sun Tzu's era.

Getting accurate, relevant information can be difficult because you're never on the front lines and there is too much data.

Leaders can get great information these days. But as former Harvard professor Richard Tedlow explains, they often just don't want to hear it.

I have been teaching and writing about business history for four decades, and what is striking about the dozens of companies and CEOs I have studied is the large number of them who have made mistakes that could and should have been avoided, not just with the benefit of hindsight, but on the basis of information available to decision makers right then and there, in real time. These mistakes resulted from individuals denying reality. [Denial: Why Business Leaders Fail to Look Facts in the Face — and What to Do About It]

So how can you avoid the eternal problems of getting and using good information?

How to wage a Sun Tzu war from your cubicle

So Sun Tzu was right — and still is. What does that mean for you and me?

Before that job interview, research the company. Before that meeting, find out who they are. Before that negotiation, research their previous deals.

I'll distill it down to four core, actionable ideas:

1. Do your homework. Information is easy to get but good information can still be elusive. Spend the time.

2. Talk to people. Maybe you don't have Sun Tzu's "spies" but lots of info you need is not online; it's in people's heads. Call them.

3. Don't get cocky. Hubris is the enemy. Confidence is great but never fall into the trap of thinking you know it all. Question yourself or, better yet, have a friend do it for you.

4. Don't give up easy. You may lack for money or manpower but who knows what crazy information the opposition might be working from? As Sun Tzu said, great leaders don't just gather information, they actively exploit and manipulate the assumptions of the other side.

Lawrence of Arabia didn't have better info than the Turks. In fact, he didn't objectively have anything better than the Turks.

But he knew one thing the Turks absolutely assumed was true: Nobody would attack Aqaba from the desert. It was suicide. It was insane.

Knowing that assumption, Lawrence had all the information he needed to surprise the enemy — and devastate them.